How to redraw widget on Flutter when a value changes? - flutter

Question

Suppose the following simple StatefulWidget example:
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatefulWidget {
#override
State<StatefulWidget> createState() {
return _MyAppState();
}
}
class _MyAppState extends State<MyApp> {
int value = 0;
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(title: Text('App Example')),
body: Row(children:[
Text("hello"),
RaisedButton(
textColor: Colors.white,
color: Colors.blue,
onPressed: (){setState(() { value+=1; });},
child: new Text("Add"),
)
]),
),
);
}
}
My main problem is: how do I redraw Text("hello") every time value changes? I'm using Text as an example, but it could be an widget that has an internal state, and I'd like to redraw it when the value changes. It does not necessarily depends on the value but I want to redraw anyways when value changes.

Answer 1

I don't have much idea ab8 it. I do this kind of stuff by wrapping it into an container and setting height and width equal to some variable.

Answer 2

If your question is if you just want to change the state of that specific widget(Example the Text widget) without disturbing the other widgets. This are some of the state management's which might help other than SetState (My personal fav. BLOC and REDUx).

Answer 3

Update this line:-
Text("hello ${value}"),
class MyApp extends StatefulWidget {
#override
State<StatefulWidget> createState() {
return _MyAppState();
}
}
class _MyAppState extends State<MyApp> {
int value = 0;
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(title: Text('App Example')),
body: Center(
child: Column(children: [
Text("hello ${value}"),
RaisedButton(
textColor: Colors.white,
color: Colors.blue,
onPressed: () {
setState(() {
value += 1;
});
},
child: new Text("Add"),
)
]),
),
),
);
}
}